Device, kit and methods for creating platelet rich plasma

ABSTRACT

A device for extracting plasma from a fluid collection tube comprising: a tubular barrel having sidewall surrounding a lumen which extends between proximal and distal ends thereof, the tubular barrel forming a tip at a distal end; a barrel seal movingly seated within the lumen of the tubular barrel, the barrel seal closing and sealing the proximal end of the tubular barrel; a tube seal having a proximal end, a distal end, and a lumen extending therebetween, the proximal end having a frustoconical or chamfered face, the tube seal having an outer diameter sized to sealingly engage with an inner surface of the fluid collection tube, and an inner diameter sized to sealingly engage with an outer surface of the tip of the tubular barrel, the tube seal mounted on the tubular barrel such that the tip of the tubular barrel extends into the tube seal lumen.

FIELD

The invention relates to a method of needless fluid transfer fromspecimen collection tubes into syringes. The invention and the methodhave applications in biological, pharmaceutical, and medical fieldswhere extraction of fluids and separation of fluid fractions take place.A preparation of platelet rich plasma (PRP) and separation of plateletpoor plasma (PPP) from whole blood are just some of many uses for thedevice that employ the method of transfer described herein.

BACKGROUND

Platelet Rich Plasma (PRP) is increasingly being used in various medicalprocedures as a catalyst for regeneration processes. PRP consists ofblood plasma with concentrated platelets, which contain various growthfactors and other cytokines that are known to stimulate regenerativeprocesses of body tissues like bone, ligaments, skin, hair and muchmore. It is obtained from the patient's own blood after red blood cells(RBC) have been removed and the platelets are concentrated in a smallvolume of plasma to 4-8 times (or more) its normal count in blood.

Platelet Poor Plasma (PPP) is used in many laboratory tests (includingdetecting antibodies in patient blood) and is obtained by removing fromwhole blood all cellular elements (red blood cells, platelets, whiteblood cells etc.).

The central part in the process of PRP preparation is prompt separationof blood fractions. Undisturbed blood left alone will separate on itsown, due to gravity forces into density layers, but usually a centrifugeis used to accelerate the process.

Generic Process

Traditionally PRP is obtained in several steps using a two-spin method.In the first step the patient's whole blood is drawn to a fluidcollection tube. See, FIGS. 1A and 1B. Next, the tube undergoes a firstspin cycle (hereinafter “first spin”) in the centrifuge and the wholeblood is separated into three broad fractions: red blood cells (RBC),buffy coat (leukocytes and platelets) and plasma. See, FIG. 1C.

In the next step, the buffy coat and plasma, collectively PlateletEnriched Plasma (PEP), which contains slightly concentrated platelets(up to two times normal blood count) are transferred to a second tube(FIG. 1D) for a second spin to further concentrate the platelets. Afterthe second spin cycle (hereinafter “second spin”) the PEP will separateinto Platelet Pallet (PP) and plasma with very few (substantially no)platelets called Platelet Poor Plasma (PPP). See, FIG. 1E.

In the final step, about two-thirds to three-quarters (⅔-¾) of PPP isremoved. It contains essentially no cellular elements and can be used invarious laboratory tests. The remaining plasma is mixed with PlateletPallet. The resulting mixture is called PRP with platelet concentrationof 4-8 (or more) times normal blood count. See, FIG. 1F.

Prior Art Shortcomings

After the first spin in the above-described process, a syringe is usedto aspirate the plasma and buffy coat through a needle, in order totransfer both into a second tube for a second spin. However, in order toreach the buffy coat located just above the RBC, a small diametersyringe and/or a long needle, are required. Most importantly, it is verydifficult to aspirate all buffy coat (layered on top of RBC), withoutalso aspirating a significant quantity of the undesired RBC.

Most commonly, commercial PRP tubes containing separating gel, are usedto collect blood. See, FIGS. 2A and 2B. While this PRP preparationprocess is somewhat easier, it also is more costly. The separating gelacts as a semi-permeable membrane. During centrifugation, RBC is forcedto pass through the gel and collects beneath it, which leaves plasma andbuffy coat physically separated above it. After centrifugation, the gelfunctions as a barrier, allowing the tube to be tilted or turned up-sidedown (to facilitate aspiration of the buffy coat and plasma), withoutcausing the RBC to mix with the buffy coat and plasma. The mixture ofbuffy coat and plasma is called Platelets Enriched Plasma (PEP). In thenext step, a syringe is used to aspirate the PEP through a needle, inorder to transfer it into a second tube to undergo a second spin. See,FIGS. 2C and 2D.

Regardless of whether tubes with separating gel are used, after thefirst spin plasma and buffy coat (PEP) need to be transferred to anothertube for a second spin, to further concentrate the platelets. Because ofthe relative complexity of those additional steps involved, the medicalpractitioners often choose to settle for PEP in their procedures, or insome cases proceed with the suboptimal PRP obtained by removing theexcess plasma from the single spin.

Present Invention Benefits

The present invention addresses the shortcomings of the existing methodsfor transferring fluid density layers from specimen tubes into syringes.With respect to PRP preparation, it is a system which makes it possibleto transfer a chosen layer of blood fraction after centrifugation, froma fluid collection tube to a syringe or a syringe-like receptacle,without the need for needles and without relying solely on negativepressure aspiration.

The present invention also eliminates the need for separating gel,because it allows a precise transfer of plasma and buffy coat to asyringe or syringe-like device, with minimal RBC contamination. This ispossible because the transfer of the lightest density fluid, which has atendency to stay on top of heavier density fluids, always takes placefirst, and the quantity being transferred can be easily controlled.

Eliminating the separating gel also eliminates the possibility ofcontaminating the plasma with gel particles; it also significantlyreduces the cost to the operator as well as to the patient. Eliminationof needles diminishes the risk of sample contamination and the risk ofaccidental needle poke that could lead to the transmission of infectiousdiseases (bacteria, viruses) to the operator.

In addition to eliminating the needles, the present invention alsoeliminates the need for a second fluid collection tube and for thetransfer syringe (used to transfer the product of the first spin (PEP)from the first tube into the second tube to perform the second spin).

The core parts of the invention are a tube seal that eliminates the needfor needles and renders the separating gel unnecessary, and a barrelthat replaces both the transfer syringe and the second-spin tube.

SUMMARY OF INVENTION

Example 1: A device for extracting plasma from a fluid collection tubecontaining a sample of whole blood which has been centrifuged to form ared blood cell layer, a buffy coat layer and a plasma layer, the devicecomprising:

a tubular barrel having sidewall surrounding a lumen which extendsbetween proximal and distal ends thereof, the tubular barrel forming atip at a distal end;

a barrel seal movingly seated within the lumen of the tubular barrel,the barrel seal closing and sealing the proximal end of the tubularbarrel;

a tube seal having a proximal end, a distal end, and a lumen extendingtherebetween, the proximal end having a frustoconical or chamfered face,the tube seal having an outer diameter sized to sealingly engage with aninner surface of the fluid collection tube, and an inner diameter sizedto sealingly engage with an outer surface of the tip of the tubularbarrel, the tube seal mounted on the tubular barrel such that the tip ofthe tubular barrel extends into the tube seal lumen;

wherein as the tubular barrel is advanced into the fluid collectiontube, the tube seal engages with inner walls of the fluid collectiontube and the outer surface of the tip of the tubular barrel, and thebarrel seal is pushed proximally by plasma flowing from the fluidcollection tube into the lumen of the tubular barrel.

Example 2: The tube seal of Example 1, wherein the tube seal is anelastomeric member having at least one sealing ring provided on theexterior surface thereof.

Example 3: The device of Examples 1-2, further comprising an elongaterod having an outer diameter which is smaller than a diameter of thelumen of the tubular barrel, the rod being removably inserted into thelumen of the tubular barrel.

Example 4: The device of Example 3, further comprising:

a tubular casing having a closed proximal end and an open distal end anda lumen extending between the closed proximal end and the open distalend;

a diameter of the rod being less than a diameter of the lumen of thetubular casing;

at least a portion of the rod coaxially received within the tubularcasing, with a gap G defined between an inner surface of the tubularcasing and an exterior surface of the rod;

a portion of the tubular barrel sidewall being coaxially received in thegap G.

Example 5: The device of Example 1, further comprising a barrel capconfigured to sealingly engage with the tip of the tubular barrel andengaging an exterior surface of the tip and/or having a plug which fitsinto the lumen of the tip.

Example 6: A kit for extracting plasma from a fluid collection tubecontaining a centrifuged sample of whole blood which has beencentrifuged to form a red blood cell layer, a buffy coat layer and aplasma layer, the kit comprising a tube seal having a lumentherethrough, the tube seal sized to movably engage with an innersurface of the fluid collection tube, the lumen of tube seal being sizedto sealingly engage with a tip of a syringe-like device.

Example 7: The kit of Example 6, further comprising:

a tubular barrel having sidewall surrounding a lumen which extendsbetween proximal and distal ends thereof, the tubular barrel forming atip at a distal end; and

a barrel seal movingly seated within the lumen of the tubular barrel,the barrel seal closing and sealing the proximal end of the tubularbarrel;

wherein the tip of the tubular barrel sized to snugly fit into andsealingly engage with the lumen of the tube seal;

wherein as the tubular barrel is advanced into the fluid collectiontube, the tube seal engages with the inner surface of the fluidcollection tube and engages with an outer surface of the tip of thetubular barrel, and the barrel seal is pushed proximally by plasmaflowing from the fluid collection tube into the lumen of the tubularbarrel.

Example 8: The kit of Example 7, comprising an elongate rod having anouter diameter which is smaller than a diameter of the lumen of thetubular barrel, the elongate rod being removably inserted into the lumenof the tubular barrel.

Example 9: The kit of Example 8, further comprising a tubular casinghaving a closed proximal end and an open distal end and a lumenextending between the closed proximal end and the open distal end.

Example 10: The kit of Example 6-9, wherein the tube seal is removablymounted to the tip of the tubular barrel.

Example 11: The kit of Example 10, further comprising a barrel capconfigured to sealingly engage with the tip of the tubular barrel andengaging an exterior surface of the tip and/or having a plug which fitsinto the lumen of the tip.

Example 12: A tube seal, comprising: an elastomeric member having alongitudinal axis, a proximal end, a distal end, and a lumen extendingtherebetween, the proximal end having a frustoconical or chamfered face,the elastomeric member having an outer diameter sized to sealinglyengage with an inner surface of a fluid collection tube, the lumen oftube seal being sized to sealingly engage with a tip of a syringe-likedevice.

Example 13: The tube seal of Example 12, further comprising at least onesealing ring provided on the exterior surface of the elastomeric member.

Example 14: A method for creating for extracting plasma from a fluidcollection tube containing a sample of whole blood which has beencentrifuged to form a red blood cell layer, a buffy coat layer and aplasma layer, comprising the steps of:

providing a tubular barrel having sidewall surrounding a lumen whichextends between proximal and distal ends thereof, the tubular barrelforming a tip at a distal end, a barrel seal movingly seated within thelumen of the tubular barrel, the barrel seal closing and sealing theproximal end of the tubular barrel, and a tube seal having a proximalend, a distal end, and a lumen extending therebetween, the proximal endhaving a frustoconical or chamfered face, the tube seal having an outerdiameter sized to sealingly engage with an inner surface of the fluidcollection tube, and an inner diameter sized to sealingly engage with anouter surface of the tip of the tubular barrel, the tip of the tubularbarrel extending into the tube seal lumen;

inserting the distal end of the tubular barrel into the fluid collectiontube such that the tube seal engages with an inner surface of the fluidcollection tube;

as the tubular barrel is advanced into the fluid collection tube pushingthe tube seal distally, plasma will flow through the tube seal lumeninto the lumen of the tubular barrel and the barrel seal is pushedproximally by the plasma flowing into the tubular barrel, wherein thetubular barrel is advanced until red blood cells just start to enterinto the tubular barrel, at which point the plasma and the buffy coathave been transferred to the tubular barrel;

the tubular barrel is withdrawn from the fluid collection tube, leavingthe tube seal engaged within the fluid collection tube along with theremaining red blood cells; and

the tubular barrel containing the plasma and buffy coat is centrifugedto separate the plasma into platelet poor plasma (PPP) and plateletpallet.

Example 15: The method of Example 14, comprising the steps of:

providing a first syringe having a first plunger movably mountedtherein;

fluidically coupling a tip of the first syringe to the tip of the firsttubular barrel; and

transferring between ⅔ and ¾ of the platelet poor plasma from thetubular barrel to the attached syringe by advancing a distal end of arod distally within the lumen of the tubular barrel toward the tip ofthe tubular barrel pushing the barrel seal distally with the rod and/orretracting the first syringe plunger.

Example 16: The method of Example 15, comprising the steps of:

disconnecting the syringe containing the platelet poor plasma from thetip of the tubular barrel, and discarding the syringe containing theplatelet poor plasma;

providing a second syringe having a second plunger movably mountedtherein;

connecting the second syringe to the tip of the tubular barrel; and

transferring the platelet poor plasma and buffy coat back-and-forthbetween the tubular barrel and the second syringe thereby mixing theplatelet poor plasma and the buffy coat to create platelet rich plasma(PRP).

Example 17: A method for creating PRP, comprising the steps:

providing a device according to Example 3;

inserting the distal end of the tubular barrel with the tube sealmounted thereon into the fluid collection tube;

advancing the tubular barrel and tube seal distally into the fluidcollection tube, wherein plasma will flow proximally through the lumenof the tube seal into the tubular barrel pushing the barrel sealproximally, wherein the tubular barrel should be advanced until redblood cells just start to enter into the tube seal; and

withdrawing the tubular barrel from the fluid collection tube leavingthe tube seal in the fluid collection tube with the remaining red bloodcells.

Example 18: The method of Example 17, further comprising the steps:

centrifuging the tubular barrel to separate the plasma and buffy coatinto platelet poor plasma and platelet pallet;

providing a first syringe having a first plunger movably mountedtherein;

fluidically coupling the first syringe to the tip of the tubular barrel;

inserting the rod into the proximal end of the tubular barrel, andadvancing the rod distally within the lumen of the tubular barrel towardthe tip pushing the barrel seal distally and transferring any residualair and ⅔-¾ of the platelet poor plasma to the first syringe, or insteadof advancing the rod, retracting the plunger of the first syringe totransfer of air and platelet poor plasma;

disconnecting the first syringe with air and the platelet poor plasmafrom the tip of the tubular barrel;

providing a second syringe having a second plunger movably mountedtherein; and

fluidically coupling the second syringe with the tip of the tubularbarrel, and transferring the platelet pallet and remaining plasmaback-and-forth between the tubular barrel and the second syringe.

Example 19: The method of Example 17, wherein after step of insertingthe distal end of the tubular barrel with the tube seal mounted thereoninto the fluid collection tube, gently removing the tubular barrel witha twisting motion leaving the tube seal engaged with the lumen of thefluid collection tube, placing the proximal end of the tubular barrel inabutment with the tube seal and advancing the tubular barrel to push oradvance the tube seal until it contacts the plasma, withdrawing theproximal end of the tubular barrel from the fluid collection tube, andplacing the distal end of the tubular barrel in sealing engagement withthe tube seal.

Example 20: A method for creating PRP, comprising the steps of:

providing a first syringe having a first plunger movably mountedtherein, the first syringe containing a specimen of whole blood;

providing a first tubular barrel having sidewall surrounding a lumenwhich extends between proximal and distal ends thereof, the firsttubular barrel forming a first tip at a distal end, a first barrel sealmovingly seated within the lumen of the first tubular barrel, the firstbarrel seal closing and sealing the proximal end of the first tubularbarrel;

fluidically coupling the first syringe to the tip of the first tubularbarrel;

transferring the specimen of whole blood from the first syringe into thefirst tubular barrel by advancing the first plunger within the firstsyringe, wherein the first barrel seal is pushed toward the proximal endof the first tubular barrel by the blood entering the first tubularbarrel;

disconnecting and discarding the first syringe;

centrifuging the first tubular barrel with the whole blood, separatingthe whole blood into a layer of red blood cells, buffy coat, and plasma;

providing a second syringe having a second plunger movably mountedtherein;

fluidically coupling the second syringe to the tip of the first tubularbarrel; and

transferring the plasma and buffy coat from the first tubular barrelinto the second syringe by retracting the second plunger within thesecond syringe or by advancing the first barrel seal within the firsttubular barrel using a rod.

Example 21: The method of Example 20, comprising:

disconnecting and discarding the first tubular barrel;

providing a second tubular barrel having sidewall surrounding a lumenwhich extends between proximal and distal ends thereof, the secondtubular barrel forming a second tip at a distal end, a second barrelseal movingly seated within the lumen of the tubular barrel, the secondbarrel seal closing and sealing the proximal end of the second tubularbarrel;

fluidically coupling the second syringe to the tip of the second tubularbarrel;

transferring the plasma and buffy coat from the second syringe into thesecond tubular barrel; and

centrifuging the second tubular barrel to separate the plasma and buffycoat into its constituent platelet poor plasma and platelet pallet.

Example 22: The method of Example 21, comprising:

providing a third syringe having a third plunger movably mountedtherein;

fluidically coupling the third syringe to the tip of the second tubularbarrel; and

transferring any residual air and ⅔-¾ of the platelet poor plasma intothe third syringe by either advancing the distal end of the rod withinthe lumen of the second tubular barrel toward the tip or retracting thethird plunger of the third syringe.

Example 23: The method of Example 22, comprising:

disconnecting and discarding the third syringe with the platelet poorplasma;

providing a fourth syringe having a fourth plunger movably mountedtherein;

fluidically couple the fourth syringe with the tip of the second tubularbarrel; and

transferring the platelet pallet and remaining platelet poor plasmaback-and-forth between the second tubular barrel and the fourth syringeto dislodge the platelet pallet from the fourth syringe and mix it withremaining plasma thereby creating plasma rich platelets.

Example 24: A method for creating PRP, comprising the steps of:

providing a fluid collection tube containing a sample of whole bloodwhich has been centrifuged to separate the whole blood into layers ofred blood cells, buffy coat, and plasma;

providing a first tubular barrel having sidewall surrounding a lumenwhich extends between proximal and distal ends thereof, the firsttubular barrel forming a tip at a distal end, a first barrel sealmovingly seated within the lumen of the first tubular barrel, the firstbarrel seal closing and sealing the proximal end of the tubular barrel;

inserting the tip of the first tubular barrel with a first tube sealmounted thereon into the fluid collection tube;

advancing the first tubular barrel within the fluid collection tube,wherein as the first tubular barrel is advanced distally into the fluidcollection tube, plasma enters into the first tubular barrel and pushesthe first barrel seal proximally, wherein the first tubular barrel isadvanced until ¾ of the plasma has been transferred into the firsttubular barrel, leaving the red blood cells, buffy coat, and ¼ of theplasma;

disconnecting and discarding the first tubular barrel with the plasma;

providing a second tubular barrel having sidewall surrounding a lumenwhich extends between proximal and distal ends thereof, the secondtubular barrel forming a tip at a distal end, a second barrel sealmovingly seated within the lumen of the second tubular barrel, thesecond barrel seal closing and sealing the proximal end of the secondtubular barrel;

inserting the tip of the second tubular barrel into the fluid collectiontube;

advancing the second tubular barrel such that the tip of the secondtubular barrel sealingly engages with the first tube seal and continuingto advance the second tubular barrel distally into the fluid collectiontube until all of the plasma and the buffy coat are transferred into thesecond tubular barrel, leaving the red blood cells;

removing the second tubular barrel from the fluid collection tube;

providing a second syringe having a second plunger movably mountedtherein;

fluidically coupling the second syringe with the tip of the secondtubular barrel; and

transferring the plasma and buffy coat back-and-forth between the secondtubular barrel and the second syringe to mix the buffy coat withremaining plasma thereby creating plasma rich platelets.

Example 25: A method for creating PRP, comprising the steps of:

providing a fluid collection tube containing a sample of whole bloodwhich has been centrifuged to separate the whole blood into layers ofred blood cells, buffy coat, and plasma;

providing a first syringe having a plunger movably mounted therein;

providing a first tube seal on a tip of the first syringe;

inserting the tip of the first syringe with the first tube seal mountedthereon into the fluid collection tube;

advancing the first syringe within the fluid collection tube, wherein asthe first syringe is advanced distally into the fluid collection tube,plasma enters into the first syringe and pushes the first plungerproximally, wherein the first syringe is advanced until ¾ of the plasmahas been transferred into the first syringe;

disconnecting and discarding the first syringe while leaving the firsttube seal mounted within the fluid collection tube;

providing a second syringe having a second plunger movably mountedtherein;

inserting a tip of the second syringe into the fluid collection tube;

advancing the second syringe until it sealingly engages with the firsttube seal and continuing to advance the second syringe distally into thefluid collection tube until all of the plasma and the buffy coat aretransferred into the second syringe; and

disconnecting the second syringe from the fluid collection tube, anddiscarding the fluid collection tube.

Example 26: A method for transferring a first layer of fluid from afluid specimen tube containing at least two layers of fluid where eachfluid had a different specific gravity, using the device of Example 1,comprising the steps of:

providing a tubular barrel having sidewall surrounding a lumen whichextends between proximal and distal ends thereof, the tubular barrelforming a tip at a distal end, a barrel seal movingly seated within thelumen of the tubular barrel, the barrel seal closing and sealing theproximal end of the tubular barrel, and a tube seal having a proximalend, a distal end, and a lumen extending therebetween, the proximal endhaving a frustoconical or chamfered face, the tube seal having an outerdiameter sized to sealingly engage with an inner surface of the fluidcollection tube, and an inner diameter sized to sealingly engage with anouter surface of the tip of the tubular barrel, the tip of the tubularbarrel extending into the tube seal lumen;

inserting the distal end of the tubular barrel into the fluid collectiontube such that the tube seal engages with an inner surface of the fluidcollection tube;

as the tubular barrel is advanced into the fluid collection tube pushingthe tube seal distally, fluid 1 will flow through the tube seal lumeninto the lumen of the tubular barrel and the barrel seal is pushedproximally by the plasma flowing into the tubular barrel, wherein thetubular barrel is advanced until fluid 2 just starts to enter into thetubular barrel, at which point the fluid 1 has been transferred to thetubular barrel;

the tubular barrel is withdrawn from the fluid collection tube, leavingthe tube seal engaged within the fluid collection tube along with fluid2.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1A shows a fluid collection tube with anticoagulant;

FIG. 1B shows the fluid collection tube of FIG. 1A with a sample ofwhole blood;

FIG. 1C shows the fluid collection tube of FIG. 1B after it has beencentrifuged

FIG. 1D shows a fluid collection tube of FIG. 1C containing plasma andbuffy coat after the red blood cells have been removed;

FIG. 1E shows the fluid collection tube of FIG. 1D after it has beencentrifuged

FIG. 1F shows the fluid collection tube of FIG. 1E after ¾ of the plasmahas been removed leaving ¼ of the plasma and the platelet pallet(collectively PRP)

FIG. 2A depicts a fluid collection tube containing separating gel andanti-coagulant

FIG. 2B depicts the fluid collection tube of FIG. 2A with a sample ofwhole blood

FIG. 2C depicts the fluid collection tube of FIG. 2B after it has beencentrifuged

FIG. 2D shows a syringe attached to the fluid collection tube of FIG. 2C

FIGS. 3A-3C are drawings illustrating examples of the tube seal in afluid collection tube;

FIGS. 4A-4D show a needleless transfer method for transferring fluidfrom a fluid collection tube into a syringe using the tube seal

FIGS. 5A-5D show a method for inserting a tube seal into a fluidcollection tube using a dispenser;

FIG. 6 shows a fully assembled view and an exploded view of device 100;

FIGS. 7A-7B are enlarged views of the tube seal;

FIGS. 8A-8D are drawings illustrating the principle of fluid transferfrom tube to syringe due to positive pressure build up in the tube;

FIGS. 9A-9D are drawings illustrating the principle of fluid transferfrom tube to syringe due to pressure drop in the syringe;

FIGS. 10A-10F depict a method for transferring at least one layer fluidfrom a collection tube 602 containing two or more layers of fluid

FIGS. 11A-11J are drawings illustrating an example method with tube andregular syringes;

FIG. 12 is an enlarged view of the barrel of device 100;

FIG. 13 is an enlarged view of the barrel seal of device 100;

FIGS. 14A-14B are enlarged views of case of device 100;

FIGS. 15A-15B are enlarged views of the cap 100;

FIG. 16 is an exploded view of an example PRP device 100;

FIGS. 17A-17B are views of the device 100 fully assembled;

FIGS. 18A-18H, 18I-1, 18I-2, 18J-1, 18J-2, 18K-1, 18K-2, 18L-1, 18L-2,and 18M are drawings illustrating an example method (with a tube and abarrel) of using device 100;

FIGS. 19A-19E, 19F-1, 19F-2, 19G-1, 19G-2, 19H-1, 19H-2, 19I-1, and19I-2 are drawings illustrating an example method (with a tube andbarrels) of using device 100; and

FIGS. 20A, 20B-1, 20B-2, 20B-3, 20C-1, 20C-2, 20C-3, 20D-1, 20D-2,20E-1, 20E-2, 20E-1, 20E-2, 20G-1, 20G-2, 20H-1, 20H-2, 20I-1, 20I-2,20J-1, 20J-2, 20K-1, 20K-2, 20L-1, 20L-2, and 20M are drawingsillustrating an example method (syringe and barrels) of using device100.

DETAILED DESCRIPTION

Described herein is a tube seal and a barrel, which may be used tofacilitate the removal of fluid layers having different density. Theexamples disclosed herein are described with reference to centrifugingwhole blood in order to separate it into its constituent components,each of which has a different density. However, one of ordinary skill inthe art will appreciate that the invention is not limited to theconstituent layers of whole blood. For instance, the invention can beused in situations/applications when a particular fraction of fluid hasto be removed and transferred from specimen tube to another syringe. Forexample, the invention may be used in the process of obtaining adiposederived tissue stromal vascular fraction (AD-tSVF) from body's fataspirate, after emulsification and separation into density layers bycentrifugation.

The Tube Seal

The tube seal may be sized to fit commercially available fluidcollection tubes. FIG. 3A shows the tube seal 108 of the presentinvention inserted into a conventional fluid collection tube 602. FIG.3B shows the tube seal 108 inserted into a conventional fluid collectiontube 602 with an anticoagulant, FIG. 3C shows the tube seal 108 insertedinto a conventional fluid collection tube 602 with both an anticoagulantand a separating gel.

FIG. 4A shows how the tube seal 108 is mounted on a distal end of aconventional syringe 180.

FIG. 4B shows how the syringe 180 with the tube seal 108 is mounted on adistal end thereof is inserted into the mouth of a conventional fluidcollection tube 602.

FIGS. 4C, 4D show the syringe 180 with the tube seal 108 is mounted on adistal end thereof is moved distally within the conventional fluidcollection tube 602 until a portion of the fluid within the fluidcollection tube 602 is transferred into the syringe 180.

In some examples it may be desirable to use a tube seal dispenser toinsert the tube seal into the fluid collection tube 602 instead ofmanually placing the tube seal in the tube with one's hand, or mountingthe tube seal on the distal end of the syringe 180. A method of using adispenser to insert the tube seal into the fluid collection tube 602using a dispenser is shown in FIGS. 5A-5D.

FIG. 5A shows how the tube seal 108 is mounted on a distal end of adispenser rod.

FIG. 5B shows how the dispenser rod with the tube seal 108 mounted on adistal end thereof is inserted into the mouth of a conventional fluidcollection tube 602.

FIGS. 5C, 5D show the syringe 180 is placed in abutment or engagementwith the tube seal inside of the fluid collection tube 602, and how thesyringe is moved distally within the conventional fluid collection tube602 until a portion of the fluid within the fluid collection tube 602 istransferred into the syringe 180.

The tube seal 108 (FIGS. 7A, 7B) has a proximal end face 108P and adistal end face 108D. In some examples, the end face 108P, 108D may havea shape 108-2, 108-3 configured to compliment or mattingly engage thetapered end face of a conventional syringe. The tube seal 108 may beformed of resilient, elastomeric material such as rubber.

An outer surface of the tube seal 108 may have a shape which mirrors theshape of the inner surface of the fluid collection tube thereby ensuringsealing engagement therebetween. In some examples, one or more raisedsealing rings 108S spanning the outer circumference (surface) of thetube seal may be provided. In the example shown in FIGS. 3A-3C, thefluid collection tube 602 and the tube seal 108 each have a circularcross-section; however, these components may have any complimentaryshaped cross-section.

As best seen in FIGS. 7A, 7B, the tube seal 108 has a lumen 108L. Insome examples, the lumen 108L has a dual taper with a first taper 108-1extending from the proximal end face 108P towards the distal end face108D and a second taper 108-2 extending from the distal end face 108Dtowards the proximal end face 108P. See, FIG. 7B. Additionally, theinner wall of the tube seal 108 which bounds or surrounds the lumen, maybe tapered. In the example depicted in FIG. 7B, the inner wall istapered such that the lumen 108L is wider at proximal end 108P than atdistal end 108D. The inner wall may have a dual taper as desired. Thetube seal 108 may be formed of an elastomeric material.

In some examples, the proximal end of the tube seal 108 is of a conicalor funnel shape to direct any residual blood through the lumen 108L tothe other side of the tube seal 108.

The tube seal 108 is sized to sealingly engage the inner surface of afluid collection tube. An outer surface of the tube seal 108 may have ashape which mirrors the shape of the inner surface of the fluidcollection tube thereby ensuring sealing engagement therebetween.

In some examples, the proximal end face 108P of the tube seal 108 mayhave a shape which compliments or mattingly engages the tapered end faceof the barrel 106.

In some examples, the proximal end of the tube seal 108 is of a conicalor funnel shape to direct any residual blood through the lumen 108L tothe other side of the tube seal 108.

The tube seal 108 may be provided by itself or as part of a kit orassembly. The kit may include a fluid collection tube, cap for fluidcollection tube, and tube seal. In some examples, the fluid collectiontube will be prefilled with an anticoagulant. In some examples, thefluid collection tube will be prefilled with an anticoagulant and aseparating gel. In some examples, the tube seal is preloaded into thefluid collection tube. In some examples, the kit may include a dispenserfor introducing the tube seal into the tube. The tube seal may also bepre-mounted on the tip of a conventional syringe or any syringe-likedevice.

Throughout this disclosure, the term syringe should be understood toencompass any syringe or syringe-like device.

As will be explained below, the tube seal 108 may be used as a connectorand adapter for transferring fluids between a fluid collection tube anda syringe, and provides a fluidic connection between the tube and thesyringe. In some examples the tube seal facilitates fluid transfer fromthe tube to the syringe due to a pressure rise in the tube (caused byadvancing the syringe distally and exerting a pressure against the tubeseal) FIGS. 8A-8D. FIG. 8A shows a fluid collection tube 602 containinga volume V1 of fluid (at ambient pressure A), a tube seal 108 and asyringe 180. FIG. 8B shows the fluid collection tube 602 and the syringe180 of FIG. 8A after the syringe 180 has been advanced distally into thefluid collection tube 602 thereby increasing the pressure of the volumeof fluid V1 (in the moment before fluid is transferred into the syringedue to the pressure gradient therebetween). FIG. 8C shows the fluidcollection tube 602 and syringe 180 of FIG. 8B after a volume V2 hasbeen transferred from the fluid collection tube 602 to the syringe 180due to the pressure gradient therebetween (in the moment before thepressure in the fluid collection tube 602 goes back to ambient. FIG. 8Dshows the fluid collection tube 602 and syringe 180 of FIG. 8C after avolume V2 has been transferred to the fluid collection tube 602 to thesyringe 180 due to the pressure gradient therebetween, after thepressure in the fluid collection tube 602 goes back to ambient.

In some examples the tube seal facilitates fluid transfer from the tubeto the syringe due to a pressure drop in the connected syringe (causedby retracting the plunger proximally and creating suction in thesyringe) FIG. 9A shows a fluid collection tube 602 containing a volumeV1 of fluid (at ambient pressure A), a tube seal 108 and a syringe 180.FIG. 9B shows the fluid collection tube 602 and the syringe 180 of FIG.9A after the plunger of syringe 180 has been retracted proximallythereby decreasing the pressure within the syringe 180 below ambient (inthe moment before fluid is transferred into the syringe due to thepressure gradient therebetween). FIG. 9C shows the fluid collection tube602 and syringe 180 of FIG. 9B after a volume V2 has been transferredfrom the fluid collection tube 602 to the syringe 180 due to thepressure gradient therebetween (in the moment before the pressure in thesyringe 180 goes back to ambient. FIG. 9D shows the fluid collectiontube 602 and syringe 180 of FIG. 9C after a volume V2 has beentransferred to the fluid collection tube 602 to the syringe 180 due tothe pressure gradient therebetween, after the pressure in the syringe180 goes back to ambient.

Generic Process of Fluid Transfer

Turning now to FIGS. 10A-10F, a method for transferring at least onelayer fluid from a collection tube 602 containing two or more layers offluid, where each layer of fluid has a different specific gravity willbe explained. The generic process used to transfer fluid from a fluidcollection tube 602 to a syringe 180 utilizing the tube seal 108 will beexplained.

In FIG. 10A, a fluid collection tube 602 containing a fluid specimen iscentrifuged to separate the fluid specimen into its constituentcomponents by density: layer 1, layer 2, and layer 3. One of ordinaryskill in the art will appreciate that the method may be used with anynumber of different density fluid layers.

In FIG. 10B, cap 602C is removed from the fluid collection tube 602, andtube seal 108 is inserted into the mouth of the fluid collection tube602. One of ordinary skill in the art will appreciate that the tube seal108 may be inserted into the fluid collection tube 602 prior to thecentrifuging step illustrated in FIG. 10A. Or the fluid collection tube602 may be equipped or supplied with the tube seal already inside thetube prior to insertion of the fluid.

In FIGS. 10C, 10D, a syringe 180 (without a needle) is inserted into themouth of the fluid collection tube 602 such that the distal tip of thesyringe 180 is placed in sealing engagement with the tube seal 108.

In FIG. 10E, as the syringe 180 is advanced distally into the fluidcollection tube 602, fluid 1 is displaced from the fluid collection tube602 into the syringe 180. The tube seal 108 seals the fluid collectiontube 602 with the syringe, enabling the transfer of fluid. It should beappreciated that the plunger of the syringe 180 may be retracted insteadof or in addition to advancing the syringe 180 distally into the fluidcollection tube 602.

If FIG. 10F, the syringe 180 containing fluid 1 may be removed from thetube seal 108 upon the transfer or displacement of the desired quantityof fluid 1. One of ordinary skill will appreciate that the syringe 180may be removed from the tube seal 108 and at any time, and a new syringeor syringe-like device 180 may be introduced to transfer desiredquantities of the remaining fluids 1, 2, 3.

Example PRP Extraction Using the Tube Seal with Ordinary Syringes(One-Spin)

Turning now to FIGS. 11A-11J, a method for transferring fluid from afluid collection tube 602 to a syringe 180 utilizing the tube seal 108will be explained. The example process pertains to the creation ofplatelet rich plasma but one of ordinary skill in the art willappreciate that the tube seal may be used generally to facilitate fluidtransfer.

In FIG. 11A, a fluid collection tube 602 containing a specimen of wholeblood is centrifuged to separate the whole blood into its constituentcomponents by density: red blood cells (RBC), buffy coat, and plasma.

In FIG. 11B, cap 602C is removed from the fluid collection tube 602, andtube seal 108 is inserted into the mouth of the fluid collection tube602. One of ordinary skill in the art will appreciate that the tube seal108 may be inserted into the fluid collection tube prior to thecentrifuging step illustrated in FIG. 11A. Or the tube may be equippedor supplied with the tube seal already inside the tube prior to fluidcollection.

In FIGS. 11C, 11D, a syringe 180 (without a needle) is inserted into themouth of the fluid collection tube 602 such that the distal tip of thesyringe 180 is placed in sealing engagement with the tube seal 108.

In FIG. 11E, as the syringe 180 is advanced distally into the fluidcollection tube 602, plasma is displaced from the fluid collection tube602 into the syringe 180 until between ⅔ and ¾ (by volume) of the plasmais transferred into the syringe. The tube seal 108 seals the fluidcollection tube 602 with the syringe, enabling the transfer of fluid. Itshould be appreciated that the plunger of the syringe 180 may beretracted instead of or in addition to advancing the syringe 180distally into the fluid collection tube 602.

In FIG. 11F, the syringe 180 with the plasma is discarded, and a fresh(empty) syringe 180 is placed into sealing engagement with the tube seal108.

In FIGS. 11G, 11H, the syringe 180 and the tube seal 108 are advanceddistally such that the remaining plasma and the buffy coat (collectivelyPRP) are transferred into the syringe 180. Again, the tube seal 108seals the fluid collection tube 602 and the syringe 180, enabling thetransfer of fluid. Also, the plunger of the syringe 180 may be retractedinstead of or in addition to advancing the syringe 180 distally into thefluid collection tube 602.

In FIGS. 11I and 11J, the syringe 180 with the PRP is withdrawn from thefluid collection tube 602, and a needle is attached to the syringe.

The aforementioned process using the tube seal 108 is an improvementover the conventional process for creating PRP, because it eliminatesthe needles, eliminates separating gel, and does not solely rely onaspiration.

Also disclosed is a system and kit for obtaining PRP using the tube seal108, as well as associated methods for separating platelet rich plasma(“PRP”) from whole blood. The system, kit, and associated methods of thepresent invention addresses several shortcomings of conventional PRPkits in that it reduces the number of components needed, eliminates theneed for a separating gel, in some examples enables separation of PRPfrom the tube after a single centrifuge spin cycle, eliminates the needfor needles thereby reducing the risk of accidental needle stick, issimpler to use, and reduces the risk of sample contamination.

The Barrel

As will be explained below, the barrel 106 is a fluid transferreceptacle equipped with a piston-like barrel seal 108. The barrel issized to fit within the lumen of a standard fluid collection tube. Thebarrel features a tip, whose outer surface is capable of sealinglyengaging with the tube seal, and an inner surface capable of sealinglyengaging with a male Luer connector of a syringe. The below mentionedprocess using the tube seal 108 with the barrel 106, is an improvementover the conventional process for creating PRP, because while the tubeseal eliminates the needles and separating gel and does not solely relyon aspiration, the barrel replaces both the transfer syringe and thesecond-spin tube.

The barrel seal 108 may be formed of an elastomeric material which maybe the same material used to form the tube seal.

FIG. 12: The barrel 106 is an elongate hollow tube having sidewallswhich surround a central lumen 106L. A proximal end 106P of the barrelis open and communicates with the lumen 106L. A distal portion of thebarrel gradually tapers narrower to a kind of Luer tip 106T. In someexamples the distal end 106D is conical shaped. The tip 106T tappersnarrower. A width of the sidewall of the barrel 106 is less than gap G,and a diameter of lumen 106L is greater than the diameter of the rod103. The distal end of the rod 103 fits into the proximal end of thebarrel 106 and the rod 103 can be loosely inserted into the lumen 106L.

The barrel 106 may have the general appearance of a conventional syringebut in some examples differs from a conventional syringe in several keyaspects. One notable difference is that barrel 106 is not meant to beequipped with a needle. The outer side of the tip 106T forms anoversized male to sealingly engage with a tube seal 108, and cannotaccommodate a needle. The inner side of the tip 106T forms a female Luerconnection configured to sealingly engage with a male Luer connection ofa regular syringe. Another notable difference is that the proximal end106P of the barrel 106 lacks the flanges or gripping portions providedon conventional syringes which are used to assist advancing the plunger.The barrel 106 is never used to inject anything. Lacking a flange andwithout the plunger rod, the barrel 106 is configured to be securelyreceived within a conventional centrifuge device.

The barrel seal 104 (FIGS. 13, 16) is movably provided within the lumen106L and will only move when pushed proximally by fluid entering thebarrel 106 through the Luer tip 106T or when advanced distally by therod 103.

As best seen in FIGS. 17A, 17B the rod 103 fits within lumen 106L whilethe barrel 106 fits in the gap G between the rod 103 and the barrel 106.

As best seen in FIGS. 15A, 15B, the barrel cap 110 is an elongate hollowtube having a central lumen 110L. In some examples, a proximal end 110Pis open and communicates with the lumen 110L, and distal end 110D isclosed. In FIG. 15A, the barrel cap 110 includes a male plug 110Xattached to an inner surface thereof which is configured to sealinglyengage the female aspects of the lumen of the tip 106T. In FIG. 15B, thebarrel cap 110 includes a female plug 110X which is configured tosealingly engage the exterior wall of the tip 106T.

FIGS. 17A, 17B show the device 100 fully assembled with the barrel seal104 within the barrel 106, the barrel 106 coaxially mounted over the rod103 and received within the casing 102, the tube seal 108 removablymounted on the tip 106T, and the barrel cap 110 mounted over the tubeseal 108 and a distal portion of the barrel 106. In FIG. 17A the distalmost part of the casing 102 overlaps the barrel cap 110, whereas in FIG.17B the distal most portion of the cap overlaps the distal most part ofthe casing 102.

FIG. 6 shows a fully assembled view and an exploded view of device 100.

It should be noted that the device 100 does not utilize needles totransfer the plasma and buffy coat out of the fluid collection tube 602and eliminates the need for using a separating gel.

FIG. 16 is an exploded view of an example device 100 which includes acasing 102 (FIGS. 14A, 14B) with its rod 103, a barrel seal 104 (FIG.13), a barrel 106 (FIG. 12), a tube seal 108 (FIGS. 7A, 7B) and a barrelcap 110 (FIGS. 15A, 15B).

FIGS. 14A, 14B: The casing 102 is an elongate hollow tube with a centrallumen 102L. In some examples, proximal end 102P of the casing 102 isclosed, and distal end 102D is open and communicates with the centrallumen 102L. A rod 103 is partially housed within the central lumen 102L.In FIG. 14A, a distal end 103D extends beyond the distal end 102D of thecasing 102. In FIG. 14B, the distal end 102D of the casing extendsbeyond the distal end 103D of the rod 103. In some examples, the rod 103is attached to the casing. For example, a proximal end 103P of the rod103 may be attached to the proximal end 102P of the casing 102. Thediameter of the lumen 102L is greater than the diameter of the rod 103such that a gap G is formed between an external surface of the rod 103and an interior wall of the casing 102.

The rod 103 may be hollow or solid. The rod 103 serves to advance thebarrel seal 104 (FIGS. 13, 16) from a proximal end 106P of the barrel106 towards the distal end 106D of the barrel. The barrel seal 104 maybe formed of an elastomeric material and fluidically seals the innersurface or lumen 106L of the barrel 106. In some examples, the barrelseal 104 abuts but is not attached to the rod 103. In this example, oncethe rod 103 has advanced the seal 104 distally, retracting the rod 103proximally will not retract the seal 104. However, in other examples,the seal 104 may be attached to the rod 103.

The rod 103 may have any shape and need not have a circularcross-section. The rod 103 must merely have sufficient structuralintegrity to advance the barrel seal 104 within the lumen 106L.

Example PRP Extraction Using the Tube Seal with the Barrel (Two-Spin)

FIGS. 18A-18M illustrate steps in a method using device 100. Some of thesteps are optional, and the order in which the steps are described arenot limiting.

In FIG. 18A, a fluid collection tube 602 containing whole blood whichhas been centrifuged to separate the whole blood into its constituentparts; namely, red blood cells, buffy coat and plasma.

In FIG. 18B, the tube cap 602C is removed from the fluid collection tube602, and the casing 102 with the rod 103 are removed from thefully-assembled device 100.

In FIG. 18C, the barrel cap 110 is removed, exposing the tube seal 108and the distal end of the barrel 106. The distal end 106D of the barrel106 with the tube seal 108 are inserted into the fluid collection tube602.

In FIG. 18D (optional), the distal end of the barrel 106 is gentlyremoved with a twisting motion leaving the tube seal 108 engaged withthe lumen of the fluid collection tube 602.

In FIG. 18E (optional), the proximal end of barrel 106 is placed inabutment with the tube seal 108 and is used to push or advance the tubeseal 108 within the fluid collection tube until the tube seal justcontacts the plasma.

In FIG. 18F (optional), the proximal end 106P of the barrel 106 iswithdrawn, the barrel 106 is flipped, and the distal end 106D is placedin sealing engagement with the tube seal 108.

In FIG. 18G, as the barrel 106 and tube seal 108 are advanced distallyinto the fluid collection tube 602, plasma will flow proximally (in theopposite direction) through lumen 108L into the hollow interior 106H ofthe barrel 106. The barrel seal 104 is pushed proximally by the fluidflowing into the barrel 106. The barrel 106 should be advanced until redblood cells just start to enter into the barrel. At that point, plasmaand the whole buffy coat have been transferred to the barrel 106. Theconical shape of the distal end of the tube seal 108 will preferentiallymove the outer part of the buffy coat to the center of the tube seal 108before red blood cells start to enter the tip 106T.

In FIG. 18H, the barrel 106 is withdrawn from the fluid collection tube602 using a twisting and pulling motion to disengage the tube seal 108from the barrel 106. In other words, as the barrel 106 is withdrawn, thetube seal 108 remains in the fluid collection tube 602 with theremaining red blood cells. The barrel cap 110 is engaged with the distalend 106D of the barrel 106.

In FIGS. 18I-1 and 18I-2, the barrel 106 containing the plasma and buffycoat (collectively PEP) is capped with device barrel cap 110 andcentrifuged (second spin cycle) to separate the PEP into its constituentparts; namely, platelet poor plasma (PPP) on the top and platelet pallet(compacted platelets) proximate the barrel seal 104. The centrifugedsample by volume comprises approximately 9/10 platelet poor plasma and1/10 platelet pallet. One of ordinary skill in the art will appreciatethat when inserting the tubular barrel into the centrifuge, the tip ofthe barrel should be pointing to the center axis of rotation.

In FIGS. 18J-1 and 18J-2, a conventional syringe 180 is attached to thebarrel 106. More particularly, the male aspect of the syringe 180interfaces with the female aspect of the barrel tip 106T. In someexamples, the rod 103 is inserted into the proximal end of the barrel106.

In FIGS. 18K-1 and 18K-2, the distal end of the rod 103 is advanceddistally within the barrel lumen 106L toward the tip 106T pushing thebarrel seal 104 distally and expelling any residual air out of thebarrel first (ideally), and then transferring ⅔-¾ of the platelets poorplasma (PPP) to the attached syringe 180. One of ordinary skill in theart will appreciate that instead of (or in addition to) advancing therod 103, the plunger of the attached conventional syringe 180 may beretracted to affect the transfer of air and PPP. The conventionalsyringe 180 with air and the platelet poor plasma is disconnected fromthe barrel tip 106T.

In FIGS. 18L-1 and 18L-2, an empty conventional syringe 180 is attachedto the Luer tip 106T. The platelet pallet and remaining plasma aretransferred back-and-forth between the barrel 106 and the syringe 180 byalternatingly pushing the rod 103 and the syringe plunger of theconventional syringe 180. This back-and-forth transfer dislodges theplatelet pallet and mixes it with remaining plasma thereby creatingplatelet rich plasma (PRP). See, FIG. 18M. Now the whole PRP istransferred to the conventional syringe 180 and is ready for use.

Example PRP Extraction Using the Barrel with Ordinary Syringes(One-Spin)

FIGS. 20A-20M illustrate an example process for creating PRP. In thisexample, the barrel 106 is the key feature, because it integrates thefunctions of both the fluid collection tube and the tube seal.

In FIG. 20A the fully assembled device 100 is disassembled by removingthe barrel cap 110, the tube seal 108, case 102 and rod 103 from thebarrel 106, leaving the barrel seal 104 within the lumen of the tube106.

In FIGS. 20B-1, 20B-2 and 20B-3 a conventional syringe 180 containingwhole blood is attached to the barrel 106, and the blood is transferredfrom the syringe 180 into the barrel 106 by advancing the plunger withinthe syringe. The barrel seal 104 is pushed toward the proximal end 106Pof the barrel 106 by the blood entering the tube 106.

In FIGS. 20C-1, 20C-2, and 20C-3 the now empty conventional syringe 108is disengaged from the barrel 106 (and discarded), and the barrel cap110 is placed in sealing engagement with the tip 106T of the barrel 106.

In FIGS. 20D-1 and 20D-2, the barrel 106 with the blood and the barrelcap 110 is centrifuged, separating the blood into a layer of red bloodcells (RBC), buffy coat, and plasma.

In FIGS. 20E-1 and 20E-2, the barrel cap 110 is removed from the barrel106, and a fresh (empty) conventional syringe 180 having a plungermovably mounted within is placed in engagement with the tip 106T of thebarrel 106.

In FIGS. 20E-1 and 20E-2 the plasma and buffy coat (collectively “PEP”)are transferred from the barrel 106 into the syringe 180. This may beaccomplished either by (a) retracting the plunger within the syringe180; or (b) by advancing the rod 103 and the barrel seal 104 within thebarrel 106. Or both, as is the case with the tube. The red blood cellsare not transferred from the barrel 106 into the syringe 180.

In FIGS. 20G-1 and 20G-2, the syringe 180 with the PEP are connected toa fresh barrel 106.

In FIGS. 20H-1 and 20H-2, the PEP is transferred from the syringe 180into the barrel 106, and barrel cap 110 is placed in sealing engagementwith the barrel tip 106T.

In FIGS. 20I-1 and 20I-2, the capped barrel 106 containing the PEP iscentrifuged (second spin cycle) to separate the PEP into its constituentparts; namely, platelet poor plasma (PPP) on the top and platelet pallet(compacted platelets) proximate the barrel seal 104. The centrifugedsample by volume comprises approximately 9/10 platelet poor plasma and1/10 platelet pallet.

In FIGS. 20J-1 and 20J-2, a conventional syringe 180 is attached to thebarrel 106. More particularly, the male aspect of the syringe interfaceswith the female aspect of the barrel tip 106T. The rod 103 is insertedinto the proximal end of the barrel 106.

In FIGS. 20K-1 and 20K-2, the distal end of the rod 103 is advanceddistally within the barrel lumen 106L toward the tip 106T pushing thebarrel seal 104 distally and expelling any residual air and ⅔-¾ of theplatelets poor plasma (PPP) to the attached syringe 180. One of ordinaryskill in the art will appreciate that instead of (or in addition to)advancing the rod 103, the plunger of the attached conventional syringe180 may be retracted to affect the transfer of air and PPP. Theconventional syringe 180 with air and the platelet poor plasma isdisconnected from the barrel tip 106T. One of ordinary skill in the artwill appreciate that the residual air could be expelled from the barrelprior to connecting the syringe 180.

In FIGS. 20L-1 and 20L-2, an empty conventional syringe 180 is attachedto the Luer tip 106T. The platelet pallet and remaining plasma istransferred back-and-forth between the barrel 106 and the syringe 180 byalternatingly pushing the rod 103 and the syringe plunger of theconventional syringe 180. This back-and-forth transfer is alsoapplicable to the methods with the tube, that also use the barrel. Thisback-and-forth transfer dislodges platelet pallet and mixes it withremaining plasma thereby creating plasma rich platelets (PRP). See, FIG.20M. Now the whole PRP is transferred to the conventional syringe 180and is ready for use.

Example PRP Extraction Using the Tube Seal with the Barrel (Single-Spin)

FIGS. 19A-19I-2 illustrate another example process for creating PRP.

In FIG. 19A, a fluid collection tube containing a sample of whole bloodis centrifuged to separate the blood into constituent layers of redblood cells (RBC), buffy coat, and plasma.

In FIG. 19B, the casing 102 and rod 103 are removed from the barrel 106,and the cap 602C is removed from the fluid collection tube 602.

In FIG. 19C, the barrel cap 110 is removed from the barrel 106, and thedistal end of the barrel 106 with the barrel seal 104 inside the lumenof the barrel and the tube seal 108 mounted on the tip 106T are insertedinto the open mouth of a fluid collection tube 602.

In FIG. 19D (optional), the barrel is removed from the fluid collectiontube with a gentle twisting motion to separate the tube seal 108 fromthe tip 106T of the barrel 106, leaving the tube seal 108 engaged withthe inner surface of the fluid collection tube 602.

In FIG. 19E (optional), the barrel 106 is flipped and the proximal end106P is inserted into the fluid collection tube 602 and placed inabutment with the tube seal 108. The barrel 106 is used to push the tubeseal distally in the fluid collection tube until it comes in contactwith the plasma. The proximal end of the barrel 106 is withdrawn, andthe distal end of the barrel 106 is re-inserted into the sealingengagement with the fluid collection tube 602.

In FIGS. 19F-1 and 19F-2 the barrel 106 is used to advance the tube seal108 within the fluid collection tube 602. As the barrel 106 is advanceddistally into the fluid collection tube 602, plasma enters into thebarrel and pushes the barrel seal 104 proximally. The barrel 106 isadvanced until between ⅔ and ¾ of the plasma has been transferred intothe barrel 106, leaving the red blood cells, buffy coat, and ¼ of theplasma. The barrel with the plasma is disengaged from the fluidcollection tube 602 and discarded.

In FIGS. 19G-1 and 19G-2, an empty barrel 106 is attached to the fluidcollection tube 602 containing red blood cells, buffy coat, andremaining plasma. The barrel 106 is advanced into the fluid collectiontube 602 until all of the plasma and the buffy coat are transferred intothe barrel 106, leaving the red blood cells.

In FIGS. 19H-1 and 19H-2 a fresh conventional syringe 180 is placed insealing engagement with the tip 106T of the barrel 106 containing theplasma and the buffy coat (collectively PRP).

In FIGS. 19I-1 and 19I-2, the plasma and buffy coat (PRP) aretransferred from the barrel into the syringe by either (a) retractingthe plunger within the syringe 180; or (b) by advancing the rod 103 andthe barrel seal 104 within the barrel 106. The barrel 106 isdisconnected from the syringe and discarded, and a needle is attached tothe syringe.

While the exemplary embodiments have been described in some detail, byway of example and for clarity of understanding, those of skill in theart will recognize that a variety of modification, adaptations, andchanges may be employed. The scope of the present invention may belimited solely by the appending claims.

The invention claimed is:
 1. A device for extracting plasma from a fluidcollection tube containing a sample of whole blood which has beencentrifuged to form a red blood cell layer, a buffy coat layer and aplasma layer, the device comprising: a tubular barrel having sidewallsurrounding a lumen which extends between proximal and distal endsthereof, the tubular barrel forming a tip at a distal end; a barrel sealmovingly seated within the lumen of the tubular barrel, the barrel sealclosing and sealing the proximal end of the tubular barrel; a tube sealhaving a proximal end, a distal end, and a lumen extending therebetween,the proximal end having a frustoconical or chamfered face, the tube sealhaving an outer diameter sized to sealingly engage with an inner surfaceof the fluid collection tube, and a diameter of the lumen sized tosealingly engage with an outer surface of the tip of the tubular barrel,the tube seal mounted on the tubular barrel such that the tip of thetubular barrel extends into the tube seal lumen; wherein as the tubularbarrel is advanced into the fluid collection tube, the tube sealsealingly engages with inner walls of the fluid collection tube and theouter surface of the tip of the tubular barrel, and the barrel seal ispushed proximally by plasma flowing from the fluid collection tube intothe lumen of the tubular barrel.
 2. The tube seal of claim 1, whereinthe tube seal is an elastomeric member having at least one raisedsealing ring provided on the exterior surface thereof.
 3. The device ofclaim 1, further comprising an elongate rod having an outer diameterwhich is smaller than a diameter of the lumen of the tubular barrel, therod being removably inserted into the lumen of the tubular barrel. 4.The device of claim 1, further comprising a barrel cap configured tosealingly engage with the tip of the tubular barrel and engaging anexterior surface of the tip and/or having a plug which fits into thelumen of the tip.
 5. A device for extracting plasma from a fluidcollection tube containing a sample of whole blood which has beencentrifuged to form a red blood cell layer, a buffy coat layer and aplasma layer, the device comprising: a tubular barrel having sidewallsurrounding a lumen which extends between proximal and distal endsthereof, the tubular barrel forming a tip at a distal end; a barrel sealmovingly seated within the lumen of the tubular barrel, the barrel sealclosing and sealing the proximal end of the tubular barrel; a tube sealhaving a proximal end, a distal end, and a lumen extending therebetween,the proximal end having a frustoconical or chamfered face, the tube sealhaving an outer diameter sized to sealingly engage with an inner surfaceof the fluid collection tube, and an inner diameter sized to sealinglyengage with an outer surface of the tip of the tubular barrel, the tubeseal mounted on the tubular barrel such that the tip of the tubularbarrel extends into the tube seal lumen; wherein as the tubular barrelis advanced into the fluid collection tube, the tube seal engages withinner walls of the fluid collection tube and the outer surface of thetip of the tubular barrel, and the barrel seal is pushed proximally byplasma flowing from the fluid collection tube into the lumen of thetubular barrel; an elongate rod having an outer diameter which issmaller than a diameter of the lumen of the tubular barrel, the rodbeing removably inserted into the lumen of the tubular barrel; a tubularcasing having a closed proximal end and an open distal end and a lumenextending between the closed proximal end and the open distal end; adiameter of the rod being less than a diameter of the lumen of thetubular casing; at least a portion of the rod coaxially received withinthe tubular casing, with a gap G defined between an inner surface of thetubular casing and an exterior surface of the rod; and a portion of thetubular barrel sidewall being coaxially received in the gap G.
 6. A kitfor extracting plasma from a fluid collection tube containing acentrifuged sample of whole blood which has been centrifuged to form ared blood cell layer, a buffy coat layer and a plasma layer, the kitcomprising: a tube seal having a lumen therethrough and a concave face,the tube seal sized to movably engage with an inner surface of the fluidcollection tube, the lumen of tube seal being sized to sealingly engagewith a tip of a tubular barrel; a tubular barrel having sidewallsurrounding a lumen which extends between proximal and distal endsthereof, the tubular barrel forming a tip at a distal end; and a barrelseal movingly seated within the lumen of the tubular barrel, the barrelseal closing and sealing the proximal end of the tubular barrel; whereinthe tip of the tubular barrel sized to snugly fit into and sealinglyengage with the lumen of the tube seal; wherein as the tubular barrel isadvanced into the fluid collection tube, the tube seal engages with theinner surface of the fluid collection tube and engages with an outersurface of the tip of the tubular barrel, and the barrel seal is pushedproximally by plasma flowing from the fluid collection tube into thelumen of the tubular barrel.
 7. The kit of claim 6, comprising anelongate rod having an outer diameter which is smaller than a diameterof the lumen of the tubular barrel, the elongate rod being removablyinserted into the lumen of the tubular barrel.
 8. The kit of claim 7,further comprising a tubular casing having a closed proximal end and anopen distal end and a lumen extending between the closed proximal endand the open distal end.
 9. The kit of claim 6, wherein the tube seal isremovably mounted to the tip of the tubular barrel.
 10. The kit of claim9, further comprising a barrel cap configured to sealingly engage withthe tip of the tubular barrel and engaging an exterior surface of thetip and/or having a plug which fits into the lumen of the tip.